In my experience as a speech-language pathologist working with parents and young children, it seems to be nearly universal that parents ask their children "Can you" questions.
Though this is common, I rarely see benefit from the use of this question form.
The "Can you" question really commands only a "yes" or "no" answer.
It literally means, "Are you able to?" As an adult, you are aware that you either can or can't ski, can or can't climb a rock wall, can or can't fix your car, can or can't cook like a chef.
, can or can't speak a foreign language.
Your response to a "Can you" question usually relates to your ability.
For a young child, especially a toddler, being asked a "Can you" question is an invitation to express "no" with regard to real or perceived skill or interest in doing the requested task.
Think about these examples: (in the doctor's office) "Can you sit up here like a big boy?" elicits a scared "NO!" (In the playroom surrounded by a huge number of toys) "Can you pick up your toys?" elicits an overwhelmed "No!" (In the kitchen when a child who doesn't talk much or all wants a snack) "Can you say, 'cracker'?" elicits a knowing and self-protective "No!" It appears that parents and other adults use "Can you" questions thinking they are enticing or encouraging young children to do something.
Asking questions in this way can really backfire with a reserved, frightened, willful, tired, or uncooperative child.
For a child who truly cannot, or believes he cannot, do something, such as to say a specific word, such a question can lead to frustration and even a tantrum.
What are some alternatives to asking "Can you" questions? I suggest that parents replace asking such questions by: Making straightforward, matter-of-fact, informative statements.

1. "It's time to put away the toys.
   Everybody clean up! First we clean up, then we go outside!" [The parent may need to participate in picking up toys, may need to guide, "You put the train pieces in this box, and I will put the blocks in this box.
   " and/or to make the process more fun by making a box "hungry" for the toys by moving the lid up and down while making "hungry" or "eating" sounds like "yum yum!", trying to "catch" the child's hand when he "feeds" the box.
   ]
2. "You are going to sit on this special table so the doctor can look in your ears, and I will sit next to you and hold your hand.
   "
3. "You want a cracker.
   Craaacker.
   Craaacker.
   I'll help you say it.
   Craaacker.
   "

Using a "Let's" statement which has a cooperative quality.

1. "Let's clean up the toys and then eat lunch.
   "
2. "Let's have you sit on this table with the paper on it so you are as high up as the doctor.
   "
3. "You want a cracker! Let me hear you say, 'Cracker.
   ' 'Craaacker'.
   "

Straightforward statements are not as likely as direct "Can you" questions to elicit a "no" response or a refusal reaction from a young child.
"Let's" or "Let me hear you" statements convey a feeling of cooperative support which often results in the child's attempt to participate.
After reading this article, I urge you to listen to discover how often you or someone else asks your child a "Can you" question, and then watch to see what kind of reaction your child has to this question type.
Listen carefully, because you may not even be aware that you are using asking this question so often.
And now I ask you, can you switch from asking "Can you" questions to making informative or encouraging statements? I hope your answer is "Yes"!